Torque low twist yarn and machine and method for producing the same



y 1962 E. H. BIGGERS 3,035,396

TORQUE LOW TWIST YARN AND MACHINE AND METHOD FOR PRODUCING THE SAME Filed Aug 21 1957 y JA L H. BIGGERS ATTORNEKS gill Unite States This invention relates to continuous filament synthetic resin yarns having stretch properties by which fabrics knitted therefrom are rendered substantially stretchable and retractable, and more particularly to a yarn of this sort to. which pronounced torque characteristics resulting in its stretch properties are imparted to the yarn by heating of the yarn and promptly thereafter drawing the heated yarn across itself. This operation is unique in the speed and ease with which it is carried out. The resulting yarn exhibits permanent and pronounced torque characteristics and the manner in which the torque characteristics are applied allows the yarn to be handled in a very rapid and simple manner directly from a producers package in which the yarn normally contains substantially no twist.

The amount of heating and related physical characteristics of the yarn produced in accordance with this invention may be varied widely by controlling the temperature of the heating device and the rate of drawing of the yarn. For example, if the yarn is heated to a relatively low temperature such as 250 F. and is drawn across a heated surface at a relatively very rapid rate such as 300 yards per minute, the yarn will exhibit a relatively high residual shrinkage. On the other hand, if the temperature of the yarn is maintained relatively high, e. g. 450 F. for example, and the yarn is drawn across the heated element at a relatively low rate, such as 40- yards per minute, then the residual shrinkage in the yarn will be relatively low. Regulation of the temperature, tension, and rate of drawing of the yarn in between these extremes will provide varying degrees of shrinkage, liveliness or torque, or other properties in the yarn. The residual shrinkage of the yarn produced in accordance with this invention enables the production of a stretch stocking or other stretch fabric that has a smooth, flat form, and this is of particular advantage in the production of seamless stretchable stockings.

When the synthetic resin yarn is drawn across the heated element, such as for example a flat heated plate, the heat thus applied apparently tends to soften the yarn but without actually melting the yarn. Other suitable forms of heating devices, such as for example a heated canister or tube may be used instead of a heated plate. It is believed that this softening effect facilitates a rapid and permanent torquing of the yarn when it is drawn across itself in an appropriate manner hereinafter described immediately after heating.

Another characteristic feature of this invention that apparently distinguishes it from prior forms of stretch yarn is the relatively high degree of torque and liveliness which are imparted to the yarn as a result of the above mentioned heating and drawing the yarn across itself and without the final resulting yarn having substantial or extensive twist. Prior methods for producing stretch yarn of marked liveliness or torque require generally twisting of the yarn a relatively large number of turns twist per inch, e.g., 15 to 50 turns per inch. The method of the present invention is believed to supply yarn having torque or liveliness at least equivalent to yarn produced by prior processes and without the necessity of introducing into the yarn an extensive number of turns twist per inch. In fact, the final yarn produced in accordance with this invention indicates little or negligible turns twist per inch and yet exhibits a marked torque or liveliness which is important to the production of torque fabrics.

The synthetic resin yarn described herein may be nylon,

atent Dacron, Orlon, dynel or any of these types of yarns that are adapted to heating and imparting torque to the yarn.

These and other features of the present invention are described in further detail below in connection with the accompanying drawings, in which:

FIG. 1 is a perspective and more or less diagrammatic illustration of the manner in which yarn is handled according to the present invention for imparting torque characteristics thereto;

FIG. 2 is an exaggerated illustration in plan of the manner in which the yarns illustrated in FIGv 1 are handied to apply the torque characteristics thereto. It should be noted that this figure is turned sideways in a clockwise direction with respect to FIG. 1, the top rollers in each pair of rollers in FIG. 1 being at the bottom of FIG. 2;

FIG. 3 is an exaggerated vertical sectional view taken along line 33 of FIG. 2 and further illustrating the handling of the yarn end illustrated at the left in FIG. 2; and

FIG. 4 is a corresponding exaggerated vertical sectional view taken along line 44 of FIG. 2 and illustrating further the handling of the yarn end at the right in FIG. 2.

FIG. 1 illustrates diagrammatically the handling of the yarn from a producers: package supply as at P and P from which yarn ends Y and Y are shown being withdrawn for handling according to the present invention in order to illustrate the manner in which the direction of the torque applied to the yarn is controlled.

As indicated in FIG. 1, the yarn ends Y and Y may be led through any suitable directing means such as guide eyes at 10 and through suitable tensioning devices as at 12 to be passed over a heated surface provided by an electric hot plate or the like as indicated at 14, at'which the yarn is subjected to sutlicient heat for softening it. In the case of nylon yarn a temperature at the hot plate .14 of the order of about 400 F. to 450 F. will normally provide proper yarn softening when regulated in relation to the Speed at which the yarn passes across the hot plate 14 which may vary in the general range from about 40 yards per minute to about 200 yards per minute. Beyond the hot plate 14, the heated yarn ends Y and Y are immediately caused to travel in a looped path over guide rollers 16 in a manner that results in pulling the yarn across itself as the respective yarn ends Y and Y are drawn beyond the rollers 16 by any suitable take-up means as indicated by the directional arrows in FIG. 1.

The torque characteristics are imparted to the yarn ends Y and Y by heating and then drawing the heated yam ends across themselves at the looped path provided between the guide rollers 16, and the arrangement of this looped path is further illustrated in FIG. 2 of the drawings in which it will be seen that the respective yarn ends Y and Y are threaded first over the top guide rollers 16', then downwardly over the paired bottom rollers 16 and upwardly inside the yarn reach between the respective pairs of rollers 16, 16 and then over the supplied yarns Y and Y ahead of the respective top rollers 16 and around both resulting reaches of the respective yarns to be drawn off by the above mentioned take-up means. The particular threading arrangement illustrated in FIG. 2 is one that has been found to be adapted for use with particular facility for the purposes of the present invention, although it should be noted that this threading arrangement is representative and subject to substantial variation as long as the impontant condition of providing for drawing the softened yarn across itself is accomplished.

It should also be noted that the direction of the torque characteristics applied to the yam ends Y and Y in the above noted manner can be controlled by selecting the direction in which'the yarns are drawn across themselves as illustrated further in FIGS. 3 and 4. As indicated by the directional arrows in FIG. 3 the yarn end Y as drawn beyond the guide rollers 16, by whatever take-up means is provided, is pulled across itself from the left side of the supplied yarn as viewed from above in the supply direction, and the result of this arrangement is to impose a left hand or Z torque direction on the yarn Y being handled. FIG. 4 shows the complementary handling of the body yarn Y in which the yarn is threaded oppositely at the guide rollers 16 with a resulting opposite right hand or S torque direction which may be selected as desired in processing the yarns being handled.

The present invention has been described in detail above for purposes of illustration only and is not intended to be limited by this description or otherwise except as defined in the appended claims.

I claim:

1. The method of applying torque characteristics to a continuous filament synthetic resin yarn which comprises softening said yarn under the influence of heat, and then subsequently and substantially immediately drawing said softened yarn around a portion of itself at a substantial angle with respect to said portion.

2. A method of producing a continuous filament synthetic resin yarn having permanent and pronounced torque characteristics which comprises passing the yarn over a surface heated sufficiently to effect softening of the yarn, then subsequently and substantially immediately forming at least one loop in said softened yarn at which the yarn is wrapped around a portion of itself with the loop being at a substantial angle with respect :to said portion, and pulling said yarn beyond the point of wrapping whereby substantial torque characteristics are imparted thereto.

3. The method of applying torque characteristics to a continuous filament synthetic resin yarn which comprises supplying said yarn in substantially untwisted form and drawing said yarn from said supply while subjecting it to softening heat and while subsequently and substantially immediately causing the softened yarn to travel in a looped path at which the yarn is pulled around a portion of itself in being drawn from said supply, said looped path being at a substantial angle with respect to said portion.

4. A continuous filament synthetic resin torque yarn produced by the method of claim 1.

5. Apparatus for producing a continuous filament synthetic resin torque yarn comprising heated means for softening the yarn and means adjacent said heated means for disposing the heated yarn so that it may be drawn around a portion of itself at a substantial angle with respect to said portion.

6. The method defined in claim 3 and further characterized in that the direction of the torque characteristics applied to said yarn is controlled by selecting the direction in which said yarn is pulled across itself at said looped path.

7. The method of applying torque characteristics to a continuous filament synthetic resin yarn which comprises softening said yarn, drawing said softened yarn through a path, and then drawing said softened yarn around a portion of the yarn in said path at a substantial angle with respect to said portion.

8. A continuous filament synthetic resin torque yarn produced by the method of claim 7.

9. The method of applying torque characteristics to a continuous filament synthetic resin yarn according to claim 7, and characterized further in that the yarn is drawn around said portion in at least one loop.

10. The method of applying torque characteristics to a continuous filament synthetic resin yarn according to claim 7, and characterized further in that the yarn is drawn around said portion in a plurality of loops.

11. The method of applying torque characteristics to a continuous filament synthetic resin yarn which comprises supplying said yarn in substantially untwisted form and drawing said yarn from said supply while subjecting it to softening heat, drawing said softened yarn from said heat through a first path, and then causing the softened yarn to travel in a looped path around a portion of the yarn in said first path, the yarn in said looped path being at a substantial angle with respect to said portion of yarn.

References Cited in the file of this patent UNITED STATES PATENTS 2,234,523 Fischer et al. Mar. 11, 1941 2,464,502 Hall et a1 Mar. 15, 1949 2,717,215 Faulkner Sept. 6, 1955 2,881,504 Billion Apr. 14, 1959 FOREIGN PATENTS 164,127 Australia July 15, 1955 746,410 Great Britain Mar. 14, 1956 Disclaimer and Dedication 3,035,396.E'arl H. Bz'ggers, Concord, N.C. TORQUE LOW TWIST YARN AND MACHINE AND METHOD FOR PRODUCING THE SAME. Patent dated May 22, 1962. Disclaimer and dedication filed July 31, 197 5, by the assignee, Patentew, Inc. Hereby disclaims and dedicates to the Public the entire remaining term of said patent.

[Oflicz'al Gazette October 21, 1975.] 

